Find a rock with a crack that can be filled with water. Put the rock with the
water-filled crack into the freezer. After it has frozen completely, repeat the experiment
until the rock eventually splits.

When water freezes, it expands and this will crack the rock into pieces. This occurs
mainly in areas that are warm during the day and freezing at night.

Acid Attack

Materials you need are:

chalk

vinegar or lemon juice (both are acids)

a container

Pour the vinegar or lemon juice over the chalk and watch it disappear slowly.

Acid rain is formed when carbon dioxide and other gases from car and factory
exhausts combine with rain. Acids can also be formed by decaying plant matter. Both of
these weather or break down rocks as shown with the chalk.